1. Field of the Invention
This invention relates to telephone or like systems and is more particularly concerned with public telephone systems of the type in which the number of calls completed by a subscriber or the number of unit values represented by such calls is recorded on some type of register device, the information from which is then used as the basis for rendering accounts.
2. Description of the Prior Art
The arrangement almost universally adopted at the present time is to make use of an electromagnetically-operated step-by-step ring counter with four or five decimal positions. Such a counter, which is on a per subscriber basis, makes one or several steps at the beginning of the conversation depending on the distance between the calling and the called parties. For long distance calls, the counter will step during the conversation with a certain frequency depending on the distance between the two parties. This system is known as periodic pulse metering.
Readings of the various counters are made at predetermined intervals, for instance monthly or quarterly, and the accounts to the subscribers are made out from the figures thus obtained. The individual reading of the meters and the preparation of the accounts is a tedious operation, even if some degree of mechanization is used as by photographing them. The picture that is taken of the panel mounted counter is then read and the reading is perforated on cards by an operator; the final bill for the customer is a copy of this card. This major disadvantage of the mechanical counters, caused by the difficulty of reproducing their position for billing the customer except by the slow and very expensive manual operation, has resulted in the expenditure of much effort to improve the system.